Paper Thin Walls
by M.M Darling
Summary: Alternate title: "I think I love you." Kate is haunted by a bad 70's song; realizations and confessions ensue. Caskett.


_**Paper Thin Walls**_

Alternate title: "I think I love you." Kate is haunted by a bad 70's song; realizations and confessions ensue. Caskett.

_A/N: Long time lurker, first time poster… This song has been stuck in my head all day, and it seemed so appropriate that I couldn't NOT write about it. Be kind. I'm normally more of a non-fiction girl._

_Timeline: I didn't mean for this to be a 47 secs/Limey fic. I SWEAR. But I was having trouble not sticking to canon, and this song is just too perfect… so yeah. My take on what has been written about 100000 times in the last week. I know, because I've read all 100000. ;-)_

_**Disclaimer: I don't even own an apartment with a dishwasher. Or an elevator. So no, no ownership here.**_

_Monday_

"I THINK I LOVE YOU, SO WHAT AM I SO AFRAID OF?"

Kate jolted awake, the words - song lyrics? Internal confession? She wasn't sure - echoing in her head. She looked around the dark bedroom, eyes landing on her alarm clock. "4:30 am, 4/2/12," the red numbers flashed. Had she missed a call from the precinct? She wouldn't be awake for any other reason, right?

"I THINK I LOVE YOU!"

A quick glance at her phone confirmed: nope, no missed calls from dispatch. Just an eerily omniscient message coming through her paper-thin walls. She groaned and slumped back onto her pillows. It took this second iteration of lyrics - yes, they were lyrics, as she could finally make out the melody - and the sound of heavy footsteps next door for her to realize what was going on.

New neighbors. They had moved in just the day before, and Kate vaguely remembered shaking their hands when she passed them in her box-lined hallway. The shuffling of tenants on the first of each month is standard fare in Manhattan, so Kate barely paid attention during these "introductions" anymore. She thinks they may have been doctors (nurses?), which would explain the early wake-up call.

Not that it made it any better. Because now she was awake, with a song stuck in her head that hit way too close to home, judging by the heavy beating of her heart.

She scrunched her eyes closed, and willed herself to go back to sleep. She even tried some of those silly breathing exercises they make you do in yoga. No luck. As she started counting to 100 in Russian (NOT because doing so reminds her of that time she used her accent to save Castle's life and he ogled her like she was the second coming of Gisele Bundchen), her phone rang. It was dispatch.

"On my way," she said, ending the call throwing another glance at her clock. 5:30 am. Crap, she could've used that hour of sleep, having been up thinking (NOT about him) later than she should have.

"I think I love you," she hummed. Crap. No. The stupid song would not get stuck in her head. She dialed his number, trying to think of any other song. Nothing came to mind. What's worse, his phone went to voicemail. She tried not to read into it - it's still the crack of dawn, after all - but he almost always answered her calls, no matter how groggy he was.

It was going to be a long day.

_Tuesday_

"BEFORE I GO INSANE I HOLD MY PILLOW TO MY HEAD AND SPRING UP IN MY BED SCREAMING OUT WORDS THE WORDS I DREAD!"

Kate awoke with a gasp, not entirely sure if it was by her own volition or if her subconscious had decided to follow the choreography of the song.

"4:30 am, 4/3/12," read her alarm clock. Was it just her, or were those red letters mocking her?

"I THINK I LOVE YOU!"

Okay, _her_ alarm clock was not mocking her. But her neighbors' alarm clock was.

"I THINK I LOVE YOU!"

"Are these walls getting thinner?" she wondered aloud, belatedly realizing that her therapist would have a field day with the double-meaning of her question. She growled, and hoisted herself out of bed. There was no sleeping now, so she was going for a nice long run, after which she was buying the best earplugs her detective salary could buy. Yesterday had shown her that she needed to have all her energy to deal with a passive-aggressive Castle, and this less-than-five-hours crap wasn't going to cut it for the rest of the week.

"I THINK I LOVE YOU!"

On second thought, maybe she should just steal her neighbors' earplugs… because two minutes and thirty seconds into this goddamned song they still CLEARLY hadn't woken up yet.

So, she slammed her door on her way out.

Just doing her neighborly duty, she thought with a smirk.

_Wednesday_

The earplugs had worked like a charm. Kate slept until her usual 7:30 am, and had woken up without some bad song from the 1970's haunting her every move. It was all such a relief that she decided to grab two coffees and two bear claws on the way to the precinct, texting Castle to come to work hungry and un-caffeinated. She had added a winky face (SO not Beckett-like, she thought) so he wouldn't think she was blowing him off, but the look he had on his face when he entered the bullpen made her realize that he thought just that.

"I got us breakfast!" she said brightly, ignoring the pit she got in her stomach when she saw his sullen face. "So now I'm only 99 coffees in the hole," she added with what she hoped was a flirty smirk.

"Thanks," he said, accepting the food with a half-smile that didn't nearly reach his eyes. "But you know you don't owe me anything."

Okay, there was a bite to that statement. Right? Or was she imagining it?

She glanced over at Esposito, who had heard the exchange and was also looking perplexed. Okay, so, not in her head. Great.

"Really, Castle, it's my pleasure," she tried again.

"Oh, I'm sure," he said quietly - though, once again, the bite came through loud and clear.

Kate sighed. She couldn't take another day of this. She was about to tell him that if he wasn't feeling well he could go home when Ryan's voice rang through the bullpen.

"Guys, we got a body. 73rd and Lex."

Kate, Esposito and Ryan jumped up immediately, while Castle looked like Ryan had told him he needed a root canal.

"You comin', Castle?" Kate asked as she threw on her coat.

"Yeah," he said slowly. "Why wouldn't I?"

"You just seem…" Kate searched for the right words. "Tired, that's all."

"Oh yeah, I'm tired all right," he muttered.

Kate didn't have the energy to push back, so she simply walked to the elevator and hoped he would follow. He did, but he didn't say anything more.

By the time they got to her car, his silence was practically killing her. She almost laughed to herself, remembering a time when she would have loved to have him this quiet. But that time passed a long time ago - didn't he know that?

She flipped on the radio as she pulled away from the precinct, hoping a decent song would break the tension, or at least give her something else to think about.

"THIS MORNING, I WOKE UP WITH THIS FEELING, I DIDN'T KNOW HOW TO DEAL WITH AND SO I JUST DECIDED TO MYSELF, I'D HIDE IT TO MYSELF AND NEVER TALK ABOUT IT!"

"JESUS!" Kate exclaimed, slamming on the brakes. Lost in the eerily - and annoyingly - familiar tune, she had almost blown through a red light.

"You okay, Beckett?" Castle asked with a raised eyebrow. If it's possible to look half-concerned, half-weary, that's exactly the expression he was wearing.

"I THINK I LOVE YOU!" the radio blared. Kate jumped, inwardly cursing that she hadn't been expecting the damn chorus to come.

"Yeah, I'm fine," she said with a shaky breath as she flipped the radio to another station.

"Not a fan of the Partridge Family?" he said, looking part amused and part - what was that other emotion? Sadness?

"Uh, I don't have particularly strong feelings towards them either way," she said. "But my new neighbors seem to like them, and they have been waking up to that song every morning this week. And thanks to incredibly thin walls, so have I."

"'I Think I Love You' has been your wake-up call each morning?" he asked, sounding the most normal - hopeful, even - he had all week.

"Ha, yep. It's been haunting me, but not by my own choice," she answered too quickly. She hadn't processed the full meaning of his question - if there was a full meaning - so she hadn't thought about the implication of her answer. His expression had darkened again, and tension refilled the car.

"Castle -" she started.

"No, I get it," he interrupted. "There are certain things you just don't want to hear."

She didn't know how to respond - was he talking about what she thinks he's talking about? - so she didn't.

They drove the rest of the way in silence.

_Thursday_

"Lanie, I'm losing my mind."

"She finally gets it!" Lanie exclaimed to the cadaver on her examining table. She looked up at Kate with a smirk. "And what prompted this revelation?"

"BecauseIThinkI'mBeingHauntedByABad70sSong?" she mumbled under her breath.

"Come again?"

Kate sighed, and reluctantly began telling Lanie everything. Each wake-up call, each resonating lyric, and every detail of the car scene from the previous day.

"Every word he's said to me recently seems laced with a double meaning, and a mean one at that!" Kate exclaimed, finishing her tale. "He's acting different and I just wish I knew what was going on."

"How long has he been acting different?" Lanie asked.

"Wait. I tell you that a song is following me everywhere I go and THAT'S your first follow-up question?"

"Yes. Because you hearing this song just means you're in love with him, which I already knew," Lanie said with that best-friend-knows-all smirk.

"Wha - But… I never -"

"And you can stop that sputtering right now," Lanie said, holding up a finger. "You're in love with Writer Boy, and just about everyone other than the two of you can see it. So I ask again: when did he start acting differently?"

"That bomb case. About halfway through, I guess."

"And what happened about halfway through the case?"

"I dunno. Gates asked him to read through eye-witness accounts, one of our leads turned out to be wrong, I interrogated that kid, Bobby Lopez…" Kate trailed off, thinking about Bobby's interrogation. Man, that kid had some nerve, trying to evade questions on the basis of trauma. Trauma. He didn't know - oh. Oh no. Oh no no no no no.

"Oh my god," Kate said.

"Care to share with the class?" Lanie said with a quirked eyebrow.

"Lanie… I screwed up. Big time."

_Friday_

By the time 7:00 pm rolled around, Kate felt like she had gone through two days instead of one. The case that had started her morning had been relatively open-and-shut, but now that she knew the reason for Castle's thinly-veiled hostility, each terse response was even more painful than the last. What's worse, she couldn't seem to get him alone for even a second. Whether by his design or fate's (fate? When had Kate Beckett started believing in fate?), she wasn't sure. All she knew is that she had waited all day to talk to him, and her window was quickly closing. He was reaching for his coat.

"Castle," she started, but faltered.

"Yes?" he said, with a slight air of impatience. She felt another stab of pain - since when is he eager to be done talking with her? Oh, right. Since he knows she lied about hearing him and probably thinks it means the worst.

"I, uh… can we talk for a second?"

"What is there to talk about?" he responded cooly, sliding an arm through his coat sleeve.

"Wait - do you mind sitting down?" she asked, hoping she didn't sound too desperate.

"I really do need to leave," he said, sliding his arm through his other sleeve.

"Okay, right. Well, I wanted to tell you - "

"I THINK I LOVE YOU, SO WHAT AM I SO AFRAID OF? I'M AFRAID THAT I'M NOT SURE OF, A LOVE THERE IS NO CURE FOR. I THINK I LOVE YOU, ISN'T THAT WHAT LIFE IS MADE OF? THOUGH IT WORRIES ME TO SAY THAT I'VE NEVER FELT THIS WAY!"

Kate stared in shock at the source of this newest transmission of the song: her phone. And on the caller ID was none other than Lanie's smiling (evil, pure evil) face.

"Lanie?" Kate hissed into the phone, her eyes pleading with Castle to just stay put for one more second.

"Girl, what are you doing answering your phone? Talk to the man, for god's sake!"

"But how did you….?"

"Goodbyeeeee!" Lanie sung, and Kate heard the call end with a resounding click.

Kate stared at her phone in amazement, and then willed herself to meet Castle's eye. He was looking at her with a fair amount of curiosity and amusement - an improvement over the hostility from just a few moments ago. But underneath it all was still a level of sadness. Kate needed that sadness to go away. She needed him to understand.

"So, um, that was Lanie."

"Yes, I heard. And your favorite song…" Castle supplied, clearly not sure of where she was going with all this. But at least he seemed willing to listen, which was a start.

"Yeah. I think she thought it would be a good idea to hijack my phone and make that her ringtone," Kate said with a nervous chuckle.

"Because you think you love her?"

"No…" Kate said slowly, knowing what she needed to say next. "Because I think I love you."

Castle was silent; his face, unreadable. Kate tried again.

"Not think - do. I do love you, Castle. And I'm sorry it took me so long to say it back. And I'm sorry it took me so long to, well, even acknowledge that you said it in the first place. But I was scared. And there were those walls. But those walls are paper thin, and nearly gone. You did that. You helped wear them down. And I still don't know if I can be everything you need me to be, but I know I love you. Do you…" Kate gulped and looked at her feet, afraid to see his face as she asked the all-important question. "Do you still love me?"

"Still?" Castle said gruffly, suddenly inches from her body. When had he gotten that close? Kate looked up at his eyes, which were gleaming and gentle and, at long last, happy. "Kate, I never once stopped loving you."

"Ohthankgod," she breathed in a rush as she launched her arms around his neck, feeling tears of relief coming to her eyes. He leaned his forehead on hers, brushing his lips first on the tip of her nose, and then on each cheek.

"Kate?" he said, hovering over her lips, "I think I'm going to kiss you now."

"Enough thinking," she murmured. "More doing…" she whispered as she closed the distance between the two.

*fin*


End file.
